Derrick supporting member



Jan. 12, 1943. A, E. CUTHRELI, 12,308,157

I DER-RIGKSUPPORTING MEMBER Filed April s, 11958 2 sheets-seef 1 Y Jan.12, 1943. A. E. cu'rHRELL 2,308,157 l DERRICK SUPPORTING MEMBER v IFiled April 8, 1938 2 ShetS-Sheeb 2 maw wm FIGA- Patented Jan. 12, 1943UNE ST nsaaicn SUPPORTING MEMBER Antum E. Cuthrell, Crowley, La.,assignor to Standard Oil Development Company, a corporation of DelawareApplication April 8, 1938, Serial No. 201,015

(Cl. 18S- 21) 3 Claims.

The present invention is directed to a derrick structure andparticularly to supporting members for the legs of a derrick.

It is an object of the present invention to provide a supporting memberfor the leg of a derrick which will afford a universal seat for the leg,thereby eliminating in a large measure the stresses ordinarily set up inthe legs of the derrick by the wind and by the loading and unloading ofheavy loads on the derrick floor.

It is a further object of the present invention to provide a supportingmember of the character described which will also serve as a skid orsled upon which the derrick can be moved over the ground, whether roughor otherwise, without th necessity for dismantling the derrick.

An additional object of the present invention is the provision of asupporting member of the character described which decreases the amountof foundation that must be laid to support the derrick.

Further objects and advantages of the present invention will appear fromthe accompanying drawings in which- Figure l is a plan view of thesupporting member of the present invention with part of its uppersurface broken away;

Figure 2 is a front elevation thereof showing the derrick leg in place;

Figure 3 is a side elevation of the structure shown in Figure 2; and

Figure 4 is a detail, partly in section, of the connection between thesupporting member and the derrick leg.

Referring to Figure 1 in detail, numeral l designates a base plate whichmay be made in any desired shape and in the drawings is bent so as toform a square bottom with upturned edges, the upper periphery of whichis in the form of a square with the corners cut away. Welded to the topof the base plate are a plurality of spaced transverse I-beams 2 withthe ends thereof cut away at 3 to accommodate the bent up edges of thebase plate. Passing through these I-beams transversely, and weldedthereto, are a plurality of tubes 4 having their ends cut away at 5 toaccommodate the upturned edges of the base plate and being weldedthereto. These crossed strengthening members are covered by a deck plate6.

wardly from the edge of the plate to which they are nearest. Welded tothe center of the deck plate is a thick metal plate 8 to the center ofwhich in turn is welded a mound 9 having a spherical surface, said moundbeing in the form of a sector of a sphere. i

Referring to Figure 4, it can be seenv that the mound has a centralcircular opening l0 through which passes a bolt IIv which is screwedinto a plate I2 having a spherical undersurface matching the outersurface of the mound 9. The plate l2 is riveted or welded to the bottomof the corners of the derrick I3 beneath the leg I4. An arcuate washerIEis arranged between the head of the bolt I I and the undersurface ofthe mound 9. Ordinarily these parts are in sliding contact and arelubricated through the Alemite fitting I6 arranged in plate I2 forcommunication with the opening I0.

As previously stated, one of the above described supporting members isplaced under each leg of the derrick. Due to the broad at undersurfaceof each supporting member, it does not require the usual derrick legfoundation which consists of a pit about ten feet square and about twoand one-half feet deep filled with layers of timbers and matting. Theonly foundation required for the above described supports is a layer ofspaced timbers under each support so as to place each of them on thesame level.

In moving the derrick from one location to another tractors are attachedto the studs on the two supporting members which face the direction inwhich the derrick is to be moved. The connection can be a single towline secured to the middle stud when a tractor is used for each skid'.When a single tractor is used a Y-line is connected to the two adjacentstuds on two skids on one side of the derrick and to the tractor.

The bevelled edges of the skids together with the swivel connectionbetween each skid and the derrick make it possible to pull the derrickon the skids over very irregular ground, since each skid can tilt in anydirection. 1n order to avoid any unusual stresses in the skid the domein the center of the skid may have a radius such that its center islocated in the neutral axis of the skid, that is, coincident with itscenter of gravity, so that the motion of the skid in its skiing actionis about this point. If the center of the dome were located above orbelow this point, the derrick weight would have to be lifted back on topof the dome by the skid as it moved over irregular ground.

A great deal of time, labor and money is saved by the utilization of theabove described supports for moving a derrick. When the drillingoperation is completed, a tractor, or more than one, if desired, issimply attached to the derrick in the manner described above and thederrick with all the equipment in place thereon is skidded across thesurface of the ground to a new location which, as previously pointedout, is prepared simply by levelling off four spots for the skids. Noparticular effort need be made to steer the derrick since the skids, dueto their symmetrical shape and a swivel connection with the derrickautomatically follow the pull of the tractors. Should one leg of thederrick leave the ground due to a dip, the bolt I I will hold the skidunder that leg to it until the dip is traversed.

From the above discussion it is apparent that there are'two aspects tothe present invention. The supporting member described possesses utilityas a supporting member, per se, without regard to its utility as a skid,in that it reduces the foundation necessary for the derrick and tends tomake the derrick self centering by equalizing the stresses in all of thelegs of the derrick due to any force applied to the derrick. When thesupporting member is used solely as a support the bolt I I can bedispensed with since this bolt serves the function of holding the skidto the derrick leg in moving over uneven'ground and of holding washer i5in place to form a closed chamber for the retention off a lubricant.When the device is used solely as a skid, on the other hand, and isbuilt for service on a flat terrain, the provision of means for allowingtilting of the skid with respect to the yderrick leg may be dispensedwith and the swivel joint replaced by y,

a simple `coupling which will permit rotation ci the skid in ahorizontal plane.

The above described construction is simply an illustration of oneembodiment of the present invention. Changes in design, size, shape andindividual elements may be apparent to those skilled in the art. Forexample, the positions of mound 9 and plate I2 can be reversed, thelatter being made part of the supporting member and the former beingmade part of the derrick leg. Such changes are contemplated Within thescope of the appended claims in which it is intended to claim the abovedescribed invention as broadly as the prior art permits.

I claim:Y

1. In a derrick construction in combination, a supporting member forsaid derrick comprising a body having an extensive undersurface andhaving on its upper surface a spherical mound, an opening in the centerof said mound, a socket on the bottom of the derrick for receiving saidmound, a stud in the center of said socket adapted to project throughthe opening in the mound, an arcuate plate adapted to fit over said studand against the underside of the opening in the mound to convert saidopening into a chamber,

. and ahead on said stud for holding said arcuate plate in position.

2. In a drilling derrick structure adapted to be skidded from onelocation to another, in combination, a supporting member for each cornerof the derrick comprising a body having a substantially fiatundersurface symmetrical with respect to its vertical axis and providedwith upturned edges on all sides, a plate formed into a spherical moundattached to the upper surface of said body, an opening in the center ofsaid plate, a socket on the bottom of a corner of the derrick forreceiving said mound, a stud projecting from the center of said sockethaving a diameter small with respect to the diameter of the opening inthe center of said plate and means carried by said stud and adapted tocooperate with the undersurface of said plate for holding said mound insaid socket.

3. In a drilling derrick structure adapted to be skidded from onelocation to another, in combination, a supporting member for each cornerof the derrick comprising a body having a smooth undersu-rface ofsymmetrical shape with upturned edges, a plate formed into a sphericalmound secured to` the upper surface of said body at its center, anopening in the center of said mound, a socket conforming to the shape ofsaid mound arranged under a cor-ner of the derrick,

a stud projecting from the center of said socketY and means carried bythe stud for holding said mound in said socket. Y

ANTUM E. CUTHRELL.

